Measurement method in which a time-of-flight mass spectrometer is used to measure the ratio of mass to charge and the abundance of ions emitted, as a result of a short pulse of laser illumination, from a sample whose analyte is contained in a matrix that assists the formation of ions.
Notes: - The matrix used for assisting the ion emission needs a strong absorbance at the laser wavelength and a low enough mass to sublime. Examples of matrices for \(\pu{337 nm}\) wavelength laser light are 2,5-dihydroxybenzoic acid (DHB), 3,5-dimethoxy-4-hydroxycinnamic acid (sinapinic acid), and α-cyano-4-hydroxycinnamic acid (CHCA).
- MALDI is used to analyse non-volatile polar biological and organic macromolecules, as well as polymers, to masses of over \(\pu{3000 ku}\).
Source:
PAC, 2020, 92, 1781. 'Glossary of methods and terms used in surface chemical analysis (IUPAC Recommendations 2020)' on page 1788 (https://doi.org/10.1515/pac-2019-0404)